Surgical connectors and instrumentation

ABSTRACT

Embodiments of the present invention are directed toward a system of apparatuses to correct spinal deformities along with associated surgical techniques. The apparatuses comprise passages or channels in which spinal rods of differing diameters may be secured to allow a surgeon to vary the diameter of rods used along the length of the spine. Additionally, embodiments of the present invention are directed toward instrumentation for reduction of spinal rods into spinal pedicle screws.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 61/646,030 filed May 11, 2012 and U.S. Provisional Application Ser.No. 61/798,414 filed Mar. 15, 2013, which are incorporated by referenceherein in their entirety.

TECHNICAL FIELD

The present disclosure relates to a system and technique for spinalsurgery. Spinal implants, including connectors, hooks, screws and rods,are used to correct spinal deformities. Screws and connectors incombination with spinal rods can align and correct deformities in thenatural spinal alignment as well as repair traumatic injury.Additionally, instrumentation for reduction of spinal rods into spinalpedicle screws is provided in the present disclosure.

BACKGROUND

Spinal fixation systems may be used in surgery to fix, adjust, and/oralign the spinal column. One type of spinal fixation system employs aspinal rod for supporting the spine and fixing, adjusting, and/oraligning the spinal column into the desired orientation. Attachment ofthe spinal rod to the spinal column has been achieved using a variety ofvertebral anchors. Vertebral anchors include screws, hooks, pins, andbolts used to engage the vertebrae and connect the spinal rod todifferent vertebrae.

The length and diameter of the spinal rod depends on the size and numberof vertebrae to be held in a desired position by the spinal fixationsystem. The size of the spinal rod also depends on the region of thespine where the spinal fixation system is used. For example, in thecervical region of the spine, where the vertebrae tend to be smaller, arelatively smaller spinal rod is used. Conversely, in the thoracicregion, where heavier loads are experienced and the vertebrae tend to belarger, a spinal rod having a relatively larger diameter is used. Thecervico-thoracic junction of the spine is typically instrumented usingspinal rods of two different diameters to accommodate anatomicaldifferences between the cervical and thoracic spine regions. Toaccommodate a spinal fixation system including spinal rods havingdifferent sizes and configurations, a rod connector may be used to joina first spinal rod and a second spinal rod together. The rod connectormay be a side-by-side connector, where the ends of the two spinal rodsare placed side-by-side and connected using a connector that spans thetwo ends, or an axial connector, which aligns the axes of the two spinalrods and connects the ends of the spinal rods together along the axialdirection. The plurality of possible spinal rod diameters in combinationwith the plurality of connector arrangements results in a surgeontypically requiring a vast array of connectors on hand in preparationfor a given spinal surgery.

The spinal rods in a spinal fixation system may necessarily be bent toconform to a desired curvature of the spinal column in one or more ofthe anatomic planes as part of a spinal fixation or corrective surgery.Attachment of spinal rods to vertebral anchors such as screws, hooks,pins, and bolts may be complicated by differing curvature of theuntreated spine and the curvature of the spinal rod. Instrumentation toforce the spinal rod into engagement with the vertebral anchors may beused. Challenges arise in utilizing instrumentation to force the spinalrod into engagement with the vertebral anchors because theinstrumentation generally must be releasably affixed to a previouslyimplanted vertebral anchor and the locking mechanism on the vertebralanchor must be engaged while maintaining the spinal rod in the correctposition. Simple engagement of the instrumentation with the vertebralanchor is desirable.

SUMMARY

In one embodiment, a medical device having a spinal rod receivingchannel and a rod retaining set screw is provided. The spinal rodreceiving channel has at least a first circular hole, a second circularhole, and a third circular hole overlapping in parallel arrangement. Thefirst circular hole, the second circular hole, and the third circularhole have offset centers disposed along a single line. The firstcircular hole forms an upper arc of the rod receiving channel; thesecond circular hole forms a middle arc of the rod receiving channel;the third circular hole forms a lower arc of the rod receiving channel;and the middle arc and the lower arc are connected by a connectingslant. The rod retaining set screw secures a spinal rod disposed in thespinal rod receiving channel into the medical device.

In another embodiment, a medical device having a plurality of spinal rodreceiving channel and a plurality of retaining set screw is provided.The spinal rod receiving channels each have at least a first circularhole, a second circular hole, and a third circular hole overlapping inparallel arrangement. The first circular hole, the second circular hole,and the third circular hole have offset centers disposed along a singleline. The first circular hole forms an upper arc of the rod receivingchannel; the second circular hole forms a middle arc of the rodreceiving channel; the third circular hole forms a lower arc of the rodreceiving channel; and the middle arc and the lower arc are connected bya connecting slant. The rod retaining set screws secures a spinal roddisposed in each of the spinal rod receiving channels into the medicaldevice.

In another embodiment, a medical device having a spinal rod receivingchannel, a rod retaining set screw, and a hook for engagement with thelamina of a vertebrae is provided. The spinal rod receiving channel hasat least a first circular hole, a second circular hole, and a thirdcircular hole overlapping in parallel arrangement. The first circularhole, the second circular hole, and the third circular hole have offsetcenters disposed along a single line. The first circular hole forms anupper arc of the rod receiving channel; the second circular hole forms amiddle arc of the rod receiving channel; the third circular hole forms alower arc of the rod receiving channel; and the middle arc and the lowerarc are connected by a connecting slant. The rod retaining set screwsecures a spinal rod disposed in the spinal rod receiving channel intothe medical device.

In another embodiment, a medical device having a spinal rod receivingchannel, a rod retaining set screw, and a lateral connector rod with adiameter of approximately 4.75 mm or 5.5 mm for engagement with a spinalpedicle screw is provided. The spinal rod receiving channel has at leasta first circular hole, a second circular hole, and a third circular holeoverlapping in parallel arrangement. The first circular hole, the secondcircular hole, and the third circular hole have offset centers disposedalong a single line. The first circular hole forms an upper arc of therod receiving channel; the second circular hole forms a middle arc ofthe rod receiving channel; the third circular hole forms a lower arc ofthe rod receiving channel; and the middle arc and the lower arc areconnected by a connecting slant. The rod retaining set screw secures aspinal rod disposed in the spinal rod receiving channel into the medicaldevice.

A another embodiment, a medical device having a first cross connectorrod hook and a second cross connector hook for securing spinal rods, twoconical screw receiving ports, and two rod retaining conical screws isprovided. The first and second cross connector rod hooks have at least afirst circular bore, a second circular bore, and a third circular borewhich in combination form a hook with an open portion. The firstcircular bore, the second circular bore, and the third circular bore areparallel and have offset centers disposed along a single line. The firstcircular bore forms an upper arc of the cross connector rod hook; thesecond circular bore forms a middle arc of the cross connector rod hook;the third circular hole forms a lower arc of the cross connector rodhook; and the middle arc and the lower arc are connected by a connectingslant. The rod retaining conical screws secure a spinal rod disposed inthe first and second cross connector rod hooks into the medical device.

In another embodiment, a medical device having a first cross connectorrod hook and a second cross connector hook for securing spinal rods, twoconical screw receiving ports, and two rod retaining conical screws isprovided. The first and second cross connector rod hooks have at least afirst circular bore, a second circular bore, and a third circular borewhich in combination form a hook with an open portion. The firstcircular bore, the second circular bore, and the third circular bore areparallel and have offset centers disposed along a single line. The firstcircular bore forms an upper arc of the cross connector rod hook; thesecond circular bore forms a middle arc of the cross connector rod hook;the third circular hole forms a lower arc of the cross connector rodhook; and the middle arc and the lower arc are connected by a connectingslant. The rod retaining conical screws secure a spinal rod disposed inthe first and second cross connector rod hooks into the medical device.The medical device further has a first linkage, a second linkage, apivot post, and a midline nut. The first linkage comprises the firstcross connector hook, one of the conical screw receiving ports and abi-axial cross connector extension rod. The second linkage comprises thesecond cross connector hook, one of the conical screw receiving portsand a bi-axial cross connector. When assembled the bi-axial crossconnector extension rod is disposed in the bi-axial cross connectorextension rod channel, the linkage retaining orifice is disposed overthe threaded post, and the midline nut is disposed on the threaded post.

In another embodiment, a medical instrument having a rod reductionassembly and a pedicle screw engaging assembly is provided. The rodreduction assembly comprises a rod reduction sleeve, a reduction rod,and an advancing knob. The reduction sleeve comprises a hollow,cylindrical shaped body having an internal reduction sleeve channel,reduction rod engagement slots on a first end, and rod engagement radiion a second end. The reduction rod comprises external reduction rodthreads on a first end and the advancing knob comprises internal threadsmatched to the external reduction rod threads. The reduction rod hasfirst and second extenders extending radial from the outer surfaceproximal a second end which engage with the reduction rod engagementslots. The pedicle screw engaging assembly has fingers for engagementwith the head of a pedicle screw, finger cam pins, an inner tube, and arelease ring. The fingers each comprise a finger hook having a fingerhook undercut, a finger slot, and a finger aperture. The finger slothave a first end distal the finger hook with a width sufficient topermit finger cam pin to slide through but not enough for substantiallateral movement transverse to the sliding direction and a second endproximal the finger hook with a larger width to form a clearance fitwith the finger cam pin. The inner tube comprises a hollow, cylindricalbody having a first inner tube end and a second inner tube end, a firstinner tube slot and a second inner tube slot diametrically opposedacross the cylindrical body, and a first finger slot and a second fingerslot diametrically opposed across the cylindrical body. The first innertube slot and the second inner tube slot are open toward the secondinner tube end and the fingers are disposed in the first finger slot andthe second finger slot with the fingers oriented to dispose the fingerhooks proximal the second inner tube end and the finger hook undercutstoward the interior of the inner tube. Movement of the release ring froma first position to a second position moves the finger cam pins from thesecond end of the finger slot to the first end of the finger slotthereby positioning the fingers for insertion of the head of a pediclescrew.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following detailed description of specific embodiments of thepresent disclosure can be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 is an isometric view of an embodiment of a dual diameterconnector with rods disposed therein;

FIG. 2A is a top view of an embodiment of a dual diameter connector;

FIG. 2B is an end view of an embodiment of a dual diameter connector;

FIG. 2C is a front section view of an embodiment of a dual diameterconnector;

FIG. 3A is a top view of an embodiment of a dual diameter connector;

FIG. 3B is an end view of an embodiment of a dual diameter connector;

FIG. 4 is a top view of an embodiment of a dual diameter connector;

FIG. 5A is a front profile view of an embodiment of a dual diameterclosed laminar hook;

FIG. 5B is a side view of an embodiment of a dual diameter closedlaminar hook;

FIG. 6 is an isometric view of an embodiment of a dual diameter openlaminar hook;

FIG. 7A is a top view of an embodiment of a dual diameter fixed crossconnector;

FIG. 7B is a front view of an embodiment of a dual diameter fixed crossconnector;

FIG. 8 is an isometric view of an embodiment of a dual diameter fixedcross connector;

FIG. 9A is a top view of an embodiment of a dual diameter closed lateralconnector;

FIG. 9B is a front view of an embodiment of a dual diameter closedlateral connector;

FIG. 9C is an isometric view of an embodiment of a dual diameter closedlateral connector;

FIG. 10A is a front view of an embodiment of a dual diameter bi-axialcross connector;

FIG. 10B is a top view of an embodiment of a dual diameter bi-axialcross connector;

FIG. 11A is a front section view of an embodiment of a first linkage ofan embodiment of a dual diameter bi-axial cross connector;

FIG. 11B is a top view of an embodiment of a first linkage of anembodiment of a dual diameter bi-axial cross connector;

FIG. 12A is a side view of an embodiment of a pivot post of anembodiment of a dual diameter bi-axial cross connector;

FIG. 12B is a front view of an embodiment of a pivot post of anembodiment of a dual diameter bi-axial cross connector;

FIG. 13A is a front section view of an embodiment of a second linkage ofan embodiment of a dual diameter bi-axial cross connector;

FIG. 13B is a top view of an embodiment of a second linkage of anembodiment of a dual diameter bi-axial cross connector;

FIG. 14A is a front view of an embodiment of a dual diameter bi-axialcross connector;

FIG. 14B is a front section view of an embodiment of a dual diameterbi-axial cross connector;

FIG. 14C is a top view of an embodiment of a dual diameter bi-axialcross connector;

FIG. 15 is an isometric view of an embodiment of a midline locking postpost of an embodiment of a dual diameter bi-axial cross connector;

FIG. 16A is a profile view of an embodiment of a rod reduction device;

FIG. 16B is a profile view of an embodiment of a rod reduction device;

FIG. 16C is a section view of an embodiment of a rod reduction device;

FIG. 17A is a profile view of an embodiment of a housing tube of a rodreduction device;

FIG. 17B is a profile view of an embodiment of a housing tube of a rodreduction device;

FIG. 17C is a section view of an embodiment of a housing tube of a rodreduction device;

FIG. 18A is a front profile view of an embodiment of an advancing knobof a rod reduction device;

FIG. 18B is a profile view of an embodiment of an advancing knob of arod reduction device;

FIG. 19A is a front profile view of an embodiment of a reduction rod ofa rod reduction device;

FIG. 19B is a section view of an embodiment of a reduction rod of a rodreduction device;

FIG. 20 is a section view of an embodiment of a cap of a rod reductiondevice;

FIG. 21A is a front profile of an embodiment of a inner tube of a rodreduction device;

FIG. 21B is a side profile of an embodiment of a inner tube of a rodreduction device;

FIG. 21C is a front section view of an embodiment of a inner tube of arod reduction device;

FIG. 21D is a top section view of an embodiment of a inner tube of a rodreduction device;

FIG. 22A is a front view of an embodiment of a retractor sleeve of a rodreduction device;

FIG. 22B is a side view of an embodiment of a retractor sleeve of a rodreduction device;

FIG. 22C is a front section view of an embodiment of a retractor sleeveof a rod reduction device;

FIG. 23 is an isometric view of an embodiment of a reduction sleeve of arod reduction device;

FIG. 24A is a front view of an embodiment of a release ring of a rodreduction device;

FIG. 24B is a section view of an embodiment of a release ring of a rodreduction device;

FIG. 25A is an isometric view of an embodiment of a finger of a rodreduction device;

FIG. 25B is a section view of an embodiment of a finger of a rodreduction device;

FIG. 25C is a top view of an embodiment of a finger of a rod reductiondevice;

FIG. 25D is a section view of an embodiment of a finger of a rodreduction device;

FIG. 26A is a front view of an embodiment of a weld sleeve of a rodreduction device;

FIG. 26B is a side view of an embodiment of a weld sleeve of a rodreduction device;

FIG. 26C is a section view of an embodiment of a weld sleeve of a rodreduction device;

FIG. 26D is a top view of an embodiment of a weld sleeve of a rodreduction device;

FIG. 27 is an isometric view of an embodiment of a finger cover of a rodreduction device;

FIG. 28A is a sub-assembly of an embodiment of a rod reduction device;

FIG. 28B is a detail view of a sub-assembly of an embodiment of a rodreduction device;

FIG. 29A is a sub-assembly of an embodiment of a rod reduction device;

FIG. 29B is a sub-assembly of an embodiment of a rod reduction device;

FIG. 30A is a sub-assembly of an embodiment of a rod reduction device;

FIG. 30B is a sub-assembly of an embodiment of a rod reduction device;

FIG. 30C is an exploded view of an embodiment of a rod reduction device;

FIG. 31 is a front profile view of an embodiment of a set screw driver;

FIG. 32A is a side view of an embodiment of a rod reduction deviceattached to a spinal pedicle screw;

FIG. 32B is a section view of an embodiment of a rod reduction deviceattached to a spinal pedicle screw;

FIG. 32C is a detail section view of an embodiment of a rod reductiondevice attached to a spinal pedicle screw;

FIG. 33A is a side view of an embodiment of a rod reduction deviceattached to a spinal pedicle screw with the reduction sleeve engaging aspinal rod;

FIG. 33B is a section view of an embodiment of a rod reduction deviceattached to a spinal pedicle screw with the reduction sleeve engaging aspinal rod;

FIG. 33C is a detail section view of an embodiment of a rod reductiondevice attached to a spinal pedicle screw with the reduction sleeveengaging a spinal rod;

FIG. 34A is a side view of an embodiment of a rod reduction deviceattached to a spinal pedicle screw, a spinal rod reduced into the spinalpedicle screw, and a rod retaining set screw inserted;

FIG. 34B is a section view of an embodiment of a rod reduction deviceattached to a spinal pedicle screw, a spinal rod reduced into the spinalpedicle screw, and a rod retaining set screw inserted;

FIG. 34C is a detail section view of an embodiment of a rod reductiondevice attached to a spinal pedicle screw, a spinal rod reduced into thespinal pedicle screw, and a rod retaining set screw inserted;

FIG. 35A is a front profile view of an embodiment of a rod reductionassembly;

FIG. 35B is a section view of an embodiment of a rod reduction assembly;

FIG. 36A is a section view of an embodiment of a provisional lockinginstrument;

FIG. 36B is a profile view of an embodiment of a provisional lockinginstrument;

FIG. 37A is a front profile view of an embodiment of a spinal pediclescrew inserter;

FIG. 37B is a section view of an embodiment of a spinal pedicle screwinserter;

FIG. 37C is a detail section view of an embodiment of a spinal pediclescrew inserter;

FIG. 38 is a front profile view of an embodiment of a spinal pediclescrew inserter;

FIG. 39 is a front profile view of an embodiment of a spinal pediclescrew;

FIG. 40A is a side profile view of an embodiment of a spinal pediclescrew;

FIG. 40B is a front profile view of an embodiment of a spinal pediclescrew;

FIG. 40C is a top profile view of an embodiment of a spinal pediclescrew; and

FIG. 40D is a section view of an embodiment of a spinal pedicle screw.

DETAILED DESCRIPTION

Referring initially to FIG. 1, an isometric view of a wedding bandinline dual diameter connector 110 with spinal rods 112, 114 disposedtherein. The wedding band inline dual diameter connector 110 illustratedin FIG. 1 specifically has a 5.5 mm diameter spinal rod 112 and a 4.75mm diameter spinal rod 114 disposed therein.

The wedding band inline dual diameter connector 110 connects two spinalrods 112, 114 in a substantially parallel orientation. The wedding bandinline dual diameter connector 110 allows a surgeon performing a spinalsurgery to utilize multiple spinal rods 112, 114 along the length of thespine in lieu of a single long rod. Use of multiple spinal rods 112, 114allows for different diameter spinal rods to be used along the length ofthe spine based on changes in anatomy. Changing diameters of spinal rods112, 114 also allows for the mechanical properties, such as stiffness,of the fixation or deformity correction to be varied along the length ofthe patient's spine.

In addition to different sized spinal rods, multiple spinal rods of thesame diameter may be connected together. For example, two 5.5 mmdiameter spinal rods 112 may be joined. Additionally, two 4.75 mmdiameter spinal rods 114 may be joined.

Referring to FIGS. 2A-2C, an embodiment of a wedding band inline dualdiameter connector 110, rod receiving channels 122 are shown. Thespecific and special geometry of the rod receiving channels 122 allowsfor both 5.5 mm diameter spinal rods 112 and 4.75 mm diameter spinalrods 114 to be secured in the rod receiving channels. The rod receivingchannels 122 are substantially a composite of three circular throughholes. The resulting rod receiving channel 122 is comprised of one upperarc 410, two middle arcs 412, two connecting slants 416, and one lowerarc 414. The upper arc 410 preferably has an approximately 2.76 mm toapproximately 3.02 mm radius. For example, a radius of 2.890 mm. Themiddle arc 412 preferably has an approximately 2.595 mm to approximately2.855 mm radius. For example, a radius of 2.725 mm. The lower arc 414preferably has an approximately 1.87 mm to approximately 2.13 mm radius.For example, a radius of 2.000 mm. The connecting slant 416 preferablyhas a length of approximately 0.638 mm to approximately 0.898 mm. Forexample, a length of 0.768 mm. The centers of the upper arc 410, themiddle arc 412, and the lower arc 414 are co-linear. The center of themiddle arc 412 is located between the center of the upper arc 410 andthe lower arc 414. The centers of the upper arc 410 and middle arc 412are preferably separated by approximately 1.00 mm to approximately 1.07mm. The centers of the lower arc 414 and middle arc 412 are preferablyseparated by approximately 1.02 mm to approximately 1.09 mm. The angleof the connecting slant 416 is preferably approximately 42° toapproximately 44° from the line formed by the centers of the upper arc410, the middle arc 412, and the lower arc 414.

Set screw receiving ports 124 are positioned in alignment with the rodreceiving channels 122. The set screw receiving ports 124 are configuredto engage with a set screw 120 through threaded engagement. Set screwreceiving threads 150 are positioned on the interior surface of the setscrew receiving ports 124 to engage with external threads on set screw120. Set screws 120 are threaded into the wedding band inline dualdiameter connector 110 and abutted against the spinal rods 112, 114 tosecure the spinal rods into the wedding band inline dual diameterconnector.

In an embodiment of the wedding band inline dual diameter connector 110,a rod receiving channel relief 126 is disposed opposite each set screwreceiving port 124. The rod receiving channel relief 126 in anembodiment is a circular through hole diametrically opposite the setscrew receiving port 124.

Referring again to FIG. 1, the spinal rods 112, 114 are illustrated astranslucent to allow the interface between the wedding band inline dualdiameter connector 110 and the spinal rods to be seen. The 5.5 mmdiameter spinal rod 112 contacts the wedding band inline dual diameterconnector 110 in a 5.5 mm contact area 116 demarcated as a shadedregion. The 4.75 mm diameter spinal rod 114 contacts the wedding bandinline dual diameter connector 110 in a 4.75 mm contact area 118demarcated as a second shaded region. Both the 5.5 mm contact area 116and the 4.75 mm contact area 118 are mirrored on the opposing surface ofthe respective spinal rod 112, 114 and connector interface (not shown).

In a specific embodiment the 5.5 mm contact area 116 is approximately32.08 mm² and the 4.75 mm contact area 118 is approximately 7.44 mm².These contact areas can vary according to the limits of the full rangeof disclosed embodiments of the rod receiving channels 122.

Referring to FIG. 3A and FIG. 3B, a top profile and end profilerespectively of an inline dual diameter connector 160 is shown. Theinline dual diameter connector 160 has the same closed rod receivingchannel 122 profile as described for the wedding band inline dualdiameter connector 110. In the inline dual diameter connector 160, asingle closed rod receiving channel 122 passes along the entirelongitudinal axis. This arrangement allows two spinal rods 112, 114 tobe abutted end to end without any lateral shift required.

Referring to FIG. 4, a domino inline dual diameter connector 180 isshown in a top profile view. The domino inline dual diameter connector180 also has a front profile matching that of the wedding band inlinedual diameter connector 110 as shown in FIG. 2A and FIG. 2C. Thearrangement of the domino inline dual diameter connector 180 is that oftwo inline dual diameter connectors 160 disposed side by side.

It is envisioned that four spinal rods 112, 114 can be secured together,wherein each single spinal rod is secured by an individual set screw 120disposed in each of the four set screw receiving ports 124. It is alsoenvisioned that two spinal rods 112, 114 can be secured in a parallelorientation with two set screws 120 securing each spinal rod. The dominoinline dual diameter connector 180 may secure any combination of 4.75 mmdiameter spinal rods 114 and 5.5 mm diameter spinal rods 112 at each ofthe set screw receiving ports 124. Non-limiting examples include two4.75 mm diameter spinal rods 114 secured with two set screws 120securing each rod, a single 4.75 mm diameter spinal rod 114 and a single5.5 mm diameter spinal rod 112 with two set screws 120 securing eachrod, two 4.75 mm diameter spinal rods 114 and two 5.5 mm diameter spinalrods 112 secured with one set screw 120 securing each rod, two 4.75 mmdiameter spinal rods 114 and one 5.5 mm diameter spinal rod 112 securedwith one set screw 120 securing each 4.75 mm diameter spinal rod and twoset screws 120 securing the 5.5 mm diameter spinal rod, and two 5.5 mmdiameter spinal rods 112 and one 4.75 mm diameter spinal rod 114 securedwith one set screw 120 securing each 5.5 mm diameter spinal rod and twoset screws 120 securing the 4.75 mm diameter spinal rod.

Referring to FIG. 5A and FIG. 5B, a front profile view and a sideprofile view respectively of a closed laminar hook 210. The closedlaminar hook 210 comprises a set screw receiving port 124, a closed rodreceiving channel 122, and a hook blade 212. The hook blade 212 may beof varying widths and lengths.

Other standard styles and sizes of hooks are envisioned. Non-limitingexamples include closed and open pedicle hooks, closed laminar hooks210, open laminar hooks 220, open thoracic hooks, open offset thoracichooks, and open offset lumbar hooks.

Referring to FIG. 6, an isometric view of an open laminar hook 220. Theopen laminar hook 220 comprises an open rod receiving saddle 222 and ahook blade 212. The hook blade 212 may be of varying widths and lengths.

The open rod receiving saddle 222 comprises the same geometry as closedrod receiving channel 122 except the upper arc 410 is not present and aportion of middle arc 412 may also be not present. In an embodiment, theupper threaded portion of the open laminar hook 220 may replicate thegeometry of any uniaxial or polyaxial spinal screw known to one skilledin the art. Additionally, in an embodiment of the open laminar hook 220the external geometry may replicate the external shape and geometry ofany uniaxial or polyaxial spinal screw known to one skilled in the art.

Referring to FIG. 7A and FIG. 7B, a top and front view respectively of afixed cross connector 300. The fixed cross connector 300 comprises across connector rod hook 322 and a conical screw 302 at each end. Theconical screw 302 retains a spinal rod 112, 114 in the respective crossconnector rod hook 322. The distance between the two cross connector rodhooks 322 may be varied to allow the fixed cross connector 300 to beattached to spinal rods 112, 114 at various lateral spacing. In selectedembodiments the distance between the centers of the two cross connectorrod hooks 322 is between approximately 10 mm and approximately 40 mm. Ina further selected embodiment the distance between the centers of thetwo cross connector rod hooks 322 is between approximately 14 mm andapproximately 36 mm. Non-limiting examples include a distance betweenthe centers of the two cross connector rod hooks 322 of approximately 14mm, approximately 16 mm, approximately 18 mm, approximately 20 mm,approximately 22 mm, approximately 24 mm, approximately 26 mm,approximately 28 mm, approximately 30 mm, approximately 32 mm,approximately 34 mm, and approximately 36 mm.

Referring to FIG. 8, an isometric view of a further embodiment of thefixed cross connector 300. In this embodiment the ends of the fixedcross connector 300 are connected by a fixed cross connector extensionrod 304. The fixed cross connector extension rod 304 may be of varyinglengths to provide a fixed cross connector 300 configured to attach tospinal rods 112, 114 at various lateral spacing. In selected embodimentsthe distance between the centers of the two cross connector rod hooks322 is between approximately 10 mm and approximately 40 mm. In a furtherselected embodiment the distance between the centers of the two crossconnector rod hooks 322 is between approximately 14 mm and approximately36 mm. Non-limiting examples include a distance between the centers ofthe two cross connector rod hooks 322 of approximately 14 mm,approximately 16 mm, approximately 18 mm, approximately 20 mm,approximately 22 mm, approximately 24 mm, approximately 26 mm,approximately 28 mm, approximately 30 mm, approximately 32 mm,approximately 34 mm, and approximately 36 mm. The fixed cross connectorextension rod 304 may also be curved or angulated to allow fixation tospinal rods 112, 114 which are not in parallel alignment. The conicalscrew receiving port 324 accepts a conical screw 302 for securing aspinal rod 112, 114 in the respective cross connector rod hook 322.

Referring to FIG. 9A, FIG. 9B, and FIG. 9C, a front profile, topprofile, and an isometric view respectively of a closed lateralconnector 190. The closed lateral connector 190 comprises a lateralconnector rod 192, a set screw receiving port 124, and a closed rodreceiving channel 122. The lateral connector 190 may be affixed to apolyaxial screw 230 [shown in FIG. 39] or a uniaxial screw with thelateral connector rod 192 disposed in the screw saddle 232. The lateralconnector rod 192 is sized to match a standard spinal rod 112, 114. Thelateral connector rod 192 is preferably circular and approximately 4.75mm or approximately 5.5 mm in diameter. The lateral connector rod 192may also be varying lengths. The lateral connector rod 192 is preferablyapproximately 15 mm to approximately 80 mm in length and more preferablyapproximately 20 mm to approximately 60 mm in length. Non-limitingexamples include a lateral connector rod 192 with a length ofapproximately 20 mm, approximately 30 mm, approximately 40 mm, andapproximately 60 mm.

Referring to FIG. 10A, a front profile view of a bi-axial crossconnector 330. The bi-axial cross connector 330 comprises a firstlinkage 336, a second linkage 334, a pivot post 332, a midline nut 338,and a pair of conical screws 302. The first linkage 336 and the secondlinkage 334 can extend along a first axis to lengthen the bi-axial crossconnector 330. Adjustment of the length along the first axis allows thebi-axial cross connector 330 to be affixed to spinal rods 112, 114laterally spaced at any distance along a continuum. This is in contrastto a fixed cross connector 300, wherein the spinal rods must belaterally spaced at approximately one of a finite number ofpredetermined distances. The first linkage 336 and second linkage 334may also rotate relative to each other about the first axis. Rotation ofthe first linkage 336 and second linkage 334 about the first axis allowsthe bi-axial cross connector 330 to be affixed to spinal rods 112, 114which are skewed in the sagittal plane. The first linkage 336 and thesecond linkage 334 are also angulated about a second axis perpendicularto the first axis. Angulation of the first linkage 336 and the secondlinkage 334 about the second axis allows the bi-axial cross connector330 to be affixed to spinal rods 112, 114 which are skewed in thecoronal plane.

Adjustment of the length of the bi-axial cross connector 330 along thefirst axis allows the bi-axial cross connector 330 to be affixed tospinal rods 112, 114 laterally spaced at any distance along a continuumwithin predetermined ranges.

Referring to FIGS. 11A and 11B, the first linkage 336 comprises a crossconnector rod hook 322, a bi-axial cross connector extension rod 342,and a bi-axial cross connector extension rod limiter 344. Crossconnector rod hook 322 comprises the same geometry as closed rodreceiving channel 122 except the upper arc 410 is not present and aportion of middle arc 412 may also be not present. The bi-axial crossconnector extension rod 342 is a round shaft with the bi-axial crossconnector extension rod limiter 344 disposed on the end. The bi-axialcross connector extension rod limiter 344 helps prevent the bi-axialcross connector extension rod 342 from disengaging from the pivot post332 during manipulation of the bi-axial cross connector 330. Thebi-axial cross connector extension rod 342 is preferably approximately10 mm to approximately 40 mm in length and more preferably approximately17 mm to approximately 32 mm in length. The bi-axial cross connectorextension rod 342 is preferably approximately 3.5 mm to approximately4.5 mm in diameter and more preferably approximately 3.9 mm toapproximately 4.1 mm in diameter. For example, the bi-axial crossconnector extension rod 342 may be 24 mm in length and 3.98 mm indiameter.

Referring to FIG. 12A and FIG. 12B, a side profile and front profilerespectively of the pivot post 332. The pivot post 332 comprises abi-axial cross connector extension rod channel 350, a threaded post 352,and a linkage retaining shoulder 354. The bi-axial cross connectorextension rod channel 350 is configured to allow the bi-axial crossconnector extension rod 342 and the bi-axial cross connector extensionrod limiter 344 to pass through unimpeded when the bi-axial crossconnector extension rod is in contact with a first surface 356.Conversely, the bi-axial cross connector extension rod channel 350 isconfigured to prohibit the bi-axial cross connector extension rod 342and the bi-axial cross connector extension rod limiter 344 to passthrough unimpeded when the bi-axial cross connector extension rod is incontact with a second surface 358, as the bi-axial cross connectorextension rod limiter catches on the pivot post 332. The threaded post352 comprises threads configured to engage with internal threads on themidline nut 338.

The first surface 356 of the bi-axial cross connector extension rodchannel 350 of the pivot post 332 preferably is an arc with a diameterof approximately 0.6 to approximately 1.4 mm larger than the diameter ofthe bi-axial cross connector extension rod 342. The second surface 358of the bi-axial cross connector extension rod channel 350 of the pivotpost 332 preferably is an arc with a diameter of approximately 0.03 toapproximately 0.30 mm larger than the diameter of the bi-axial crossconnector extension rod 342. For example, as in the previous example,the bi-axial cross connector extension rod 342 may be 3.98 mm indiameter and the diameter of the arc of the first surface 356 may be4.98 mm and the diameter of the second surface 358 may be 4.02 mm.

Referring to FIG. 13A and FIG. 13B, a front profile view and a topprofile view respectively of the second linkage 334. The second linkage334 comprises a cross connector rod hook 322, a conical screw receivingport 324 with conical screw receiving threads 326, and a bi-axial crossconnector extension plank 346 having a linkage retaining orifice 340.The linkage retaining orifice 340 engages with the linkage retainingshoulder 354 of the pivot post 332. The bi-axial cross connectorextension plank 346 is a flat strip extending away from the conicalscrew receiving port 324 and cross connector rod hook 322. The bi-axialcross connector extension plank 346 is preferably approximately 10 mm toapproximately 40 mm in length and more preferably approximately 17 mm toapproximately 32 mm in length. The length of the bi-axial crossconnector extension plank 346 is the length of the thinned portion ofthe second linkage 334. For example, the bi-axial cross connectorextension plank 346 may be approximately 17 mm in length, approximately18 mm in length, approximately 20 mm in length, approximately 24 mm inlength, and approximately 32 mm in length.

When assembled, the midline nut 338 presses the second linkage 334toward the linkage retaining shoulder 354 which in turn presses thesecond linkage into the bi-axial cross connector extension rod 342 whichis passed through the bi-axial cross connector extension rod channel350. The compressive force of the midline nut 338, in conjunction withfrictional forces, prevent the bi-axial cross connector 330 fromextending along the first axis, rotating about the first axis, orangulating about the second axis.

Referring again to FIG. 10A, a front profile of the bi-axial crossconnector 330 in an extended configuration. The bi-axial cross connector330 can secure both the 5.5 mm diameter spinal rod 112 and the 4.75 mmdiameter spinal rod 114. The 5.5 mm diameter spinal rod 112 is shown inFIG. 10A in the cross connector rod hook 322 in an unsecuredconfiguration as the conical screw 302 is not fully advanced andpressing the spinal rod into the cross connector rod hook.

Referring to FIG. 10B, a top profile of the bi-axial cross connector 330in a retracted configuration. The conical screw 302 has a hexalobularinternal driving feature.

In an embodiment of the bi-axial cross connector 330, the range ofadjustment afforded by the different lengths of the bi-axial crossconnector extension rod 342 and the bi-axial cross connector extensionplank 346 allows for the bi-axial cross connector 330 to be adjustedfrom approximately 30 mm to approximately 70 mm spacing between thecenterlines of spinal rods 112/114 disposed in the cross connector rodhooks 322. In an embodiment of the bi-axial cross connector 330, spacingbetween the centerlines of spinal rods 112/114 disposed in the crossconnector rod hooks 322 may be adjusted from approximately 34 mm toapproximately 37 mm. In a further embodiment of the bi-axial crossconnector 330, spacing between the centerlines of spinal rods 112/114disposed in the cross connector rod hooks 322 may be adjusted fromapproximately 35 mm to approximately 39 mm. In a further embodiment ofthe bi-axial cross connector 330, spacing between the centerlines ofspinal rods 112/114 disposed in the cross connector rod hooks 322 may beadjusted from approximately 37 mm to approximately 43 mm. In a furtherembodiment of the bi-axial cross connector 330, spacing between thecenterlines of spinal rods 112/114 disposed in the cross connector rodhooks 322 may be adjusted from approximately 41 mm to approximately 51mm. In a further embodiment of the bi-axial cross connector 330, spacingbetween the centerlines of spinal rods 112/114 disposed in the crossconnector rod hooks 322 may be adjusted from approximately 49 mm toapproximately 67 mm. The combination of the multiple specificallydisclosed embodiments of the bi-axial cross connector 330 allows for abi-axial cross connector 330 to be selected suitable for securing spinalrods 112/114 spaced anyplace along the continuum of approximately 34 mmto approximately 67 mm.

Referring to FIG. 14A, an embodiment of a bi-axial cross connector 330.The bi-axial cross connector 330 comprises a first linkage 336, a secondlinkage 334, a midline locking post 370, a midline locking screw 339,and a pair of conical screws 302. The first linkage 336 and the secondlinkage 334 can extend along a first axis to lengthen the bi-axial crossconnector 330. Adjustment of the length along the first axis allows thebi-axial cross connector 330 to be affixed to spinal rods 112, 114laterally spaced at any distance along a continuum. This is in contrastto a fixed cross connector 300, wherein the spinal rods must belaterally spaced at approximately one of a finite number ofpredetermined distances. The first linkage 336 and second linkage 334may also rotate relative to each other about the first axis. Rotation ofthe first linkage 336 and second linkage 334 about the first axis allowsthe bi-axial cross connector 330 to be affixed to spinal rods 112, 114which are skewed in the sagittal plane. The first linkage 336 and thesecond linkage 334 are also angulated about a second axis perpendicularto the first axis. Angulation of the first linkage 336 and the secondlinkage 334 about the second axis allows the bi-axial cross connector330 to be affixed to spinal rods 112, 114 which are skewed in thecoronal plane.

Referring to FIGS. 14A and 14B, the first linkage 336 comprises a crossconnector rod hook 322, a bi-axial cross connector extension rod 342,and a bi-axial cross connector extension rod limiter 344. Crossconnector rod hook 322 comprises the same geometry as closed rodreceiving channel 122 except the upper arc 410 is not present and aportion of middle arc 412 may also be not present. The bi-axial crossconnector extension rod 342 is a round shaft with the bi-axial crossconnector extension rod limiter 344 disposed on the end. In anembodiment, the bi-axial cross connector extension rod limiter 344 is apin projecting beyond the diameter of the bi-axial cross connectorextension rod 342. The bi-axial cross connector extension rod limiter344 helps prevent the bi-axial cross connector extension rod 342 fromdisengaging from the midline locking post 370 during manipulation of thebi-axial cross connector 330. The bi-axial cross connector extension rodlimiter 344 is preferably installed in the bi-axial cross connectorextension rod 342 subsequent to passing though the midline locking post370 during the manufacturing and assembly process. The bi-axial crossconnector extension rod limiter 344 is preferably sized such thatremoval of the bi-axial cross connector extension rod 342 from themidline locking post 370 is not feasible.

Referring to FIG. 15, an embodiment of the midline locking post 370 usedin the embodiment of the bi-axial cross connector 330 shown in FIGS.14A-14C is shown. The midline locking post 370 comprises a bi-axialcross connector extension rod passage 374, a threaded locking screwreceiver 376, and a locking post retention flange 372. The bi-axialcross connector extension rod passage 374 is configured to allow thebi-axial cross connector extension rod 342 to pass through unimpeded butprevent the bi-axial cross connector extension rod limiter 344 frompassing through. The threaded locking screw receiver 376 comprisesinternal threads configured to engage with external threads on themidline locking screw 339. The locking post retention flange 372 retainsthe midline locking post 370 in the second linkage prior to securingwith the midline locking screw.

The second linkage 334 comprises a cross connector rod hook 322, aconical screw receiving port 324 with conical screw receiving threads326, and a bi-axial cross connector extension plank 346 having a linkageretaining orifice 340. The linkage retaining orifice 340 has a linkageretention flange 378 disposed around the periphery of the linkageretaining orifice 340. The linkage retention flange 378 engages with thelocking post retention flange 372.

When assembled, the midline locking screw 339 pulls the midline lockingpost 370 upward. The movement of the midline locking post 370 moves thefirst linkage 336 upward as well and compresses the first linkage 336against the second linkage 334. The compressive force of the midlinelocking screw 339 and the midline locking post 370 pulling the secondlinkage 334 and the first linkage 336 together, in conjunction withfrictional forces, prevent the bi-axial cross connector 330 fromextending along the first axis, rotating about the first axis, orangulating about the second axis.

Referring to FIG. 39, a front profile of a polyaxial screw 230. Thepolyaxial screw 230 comprises a screw saddle 232 for receiving a spinalrod 112, 114 or lateral connector rod 192 for example. The rod receivinggeometry of the screw saddle 232 is envisioned being configured to matchthe rod receiving geometry of the open rod receiving saddle 222 of theopen laminar hook 220 for acceptance of multiple diameter spinal rodsincluding a 5.5 mm diameter spinal rod 112 or a 4.75 mm diameter spinalrod 114. Uniaxial screws with a similar rod receiving geometry forsecuring multiple diameter spinal rods 112, 114 are also envisioned.

While reference is made throughout this disclosure to dual-diameterconnectors, dual-diameter hooks, and dual-diameter screws, it isenvisioned that the technique used to allow acceptance of two diametersof rods can be modified to allow three or more diameters of rods.

Referring to FIGS. 16A-16C, a rod reduction device 600 is shown. FIG.16C is a longitudinal cross sectional view of reduction device 600 takenalong section line, N-N. In the illustrative embodiment shown, reductiondevice 600 includes an housing tube 501, advancing knob 502, reductionrod 503, cap 504, inner tube 505, retractor sleeve 506, reduction sleeve507, release ring 508, release ring screw 509, fingers 510, fingersprings 511, spring hinge pins 513, finger cam pins 514, finger hingepins 515, weld sleeve 516, release spring 517, a plurality of ballbearings 518, and finger cover 519. When assembled together, thesecomponents form reduction device 600, which comprises a hollow,cylindrical shaped assembly having a first end 602 and a second end 604.First end 602 includes a first assembly opening 606, and second end 604includes a second assembly opening 608. Each of the components set forthabove will be individually described below herein and shown in separatefigures. In addition, it will be shown and described below herein howeach of the components of reduction device 600 are interconnected and,once assembled, how reduction device 600 works in operation.

Referring to FIGS. 17A-17C, housing tube 501 of reduction device 600 isshown. Housing tube 501 comprises a hollow, housing tube body 520,having a housing tube first end 522 and a second end 524 oppositehousing tube first end 522. Housing tube first end 522 is shaped. Inthis example, housing tube first end 522 has a hexagonal shape.Additionally, in this example housing tube first end 522 compriseshousing tube engagement slots 521. Also, housing tube first end 522includes internal housing tube threads 525. Housing tube first end 522also comprises a first housing tube opening 616, and second end 524comprises a second housing tube opening 618. Housing tube body 520includes an internal housing tube channel 619 that connects first andsecond outer tube openings 616/618, respectively. Housing tube body 520includes at second end 524 two diametrically opposed housing tube slots526, each running from the second end 524 longitudinally along at leasta portion of housing tube body 520. Housing tube slots 526 furtherinclude a narrow portion 527 connected to a wide portion 528.

Housing tube body 520 also includes diametrically opposed second housingtube slots 529 disposed at second end 524, but circumferentially offset90° from housing tube slots 526. Second housing tube slots 529 run fromsecond end 524 longitudinally along at least a portion of housing tubebody 520. Optionally, housing tube body 520 includes a gripping sectionsuch as a medium diamond knurl 523 etched into a surface of housing tubebody 520.

Referring to FIGS. 18A and 18B, advancing knob 502 of reduction device600 is shown. Advancing knob 502 comprises a hollow, advancing knob body530, having an advancing knob first end 532 and an advancing knob secondend 534 opposite advancing knob first end 532. Advancing knob first end532 is shaped. In this example, advancing knob first end 532 has ahexagonal shape. Advancing knob body 530 also includes an advancing knobannular ring 538 extending therefrom and disposed between a midpoint ofadvancing knob body 530 and advancing knob first end 532. Advancing knobbody 530 includes internal advancing knob threading 531 on a portion ofits internal surface. In this example, internal advancing knob threading531 is disposed from advancing knob second end 534 to just beyond themidpoint of advancing knob body 530 along the internal surface ofadvancing knob body 530. Advancing knob annular ring 538 furtherincludes an advancing knob bearing well 539 that is disposed withinadvancing knob annular ring 538 annularly about the circumference ofadvancing knob body 530. Advancing knob first end 532 also comprises afirst advancing knob opening 626, and advancing knob second end 534comprises a second advancing knob opening 628. Advancing knob body 530includes an internal advancing knob channel 629 that connects first andsecond knob openings 626/628, respectively.

Referring to FIGS. 19A and 19B, reduction rod 503 of reduction device600 is shown. Reduction rod 503 comprises a hollow, cylindrical shapedreduction rod body 540, having a first reduction rod end 542 and asecond reduction rod end 544 opposite first reduction rod end 542. Firstreduction rod end 542 comprises a first reduction rod opening 543, andsecond reduction rod end 544 comprises a second reduction rod opening545. Reduction rod body 540 includes an internal reduction rod channel547 that connects first and second reduction rod openings 543/545,respectively. First reduction rod end 542 comprises external reductionrod threads 541 disposed on a portion of the outer surface of reductionrod body 540. A first extender 548 a extends radially from the outersurface of reduction rod body 540 adjacent second reduction rod end 544.A second extender 548 b extends radially from the outer surface ofreduction rod body 540 adjacent second reduction rod end 544 anddiametrically opposed to first extender 548 a. Reduction rod body 540also comprises an annular bulbous portion 546 disposed adjacent themidpoint of reduction rod body 540, closer to second reduction rod end544. Annular bulbous portion 546 has an increased outer diametercompared to the rest of reduction rod body 540.

Referring to FIG. 20, cap 504 of reduction device 600 is shown. Cap 504comprises a hollow, cylindrical-shaped cap body 550, having a first capend 552 and a second cap end 554 opposite first cap end 552. First capend 552 comprises a first cap opening 556, second cap end 554 comprisesa second cap opening 558, and cap body 550 includes an internal capchannel 557 that connects first cap opening 556 to second cap opening558. Also, second cap end 554 includes external cap threads 551 disposedon the outer surface of cap body 550 and a substantially hemisphericalchannel disposed around the second cap opening 558 to form a cap bearingwell 555.

Referring to FIGS. 21A-21D, inner tube 505 of reduction device 600 isshown. Inner tube 505 comprises a hollow, cylindrical shaped inner tubebody 560, having a first inner tube end 562 and a second inner tube end564 opposite first inner tube end 562. First inner tube end 562comprises a first inner tube opening 566, and second inner tube end 564comprises a second inner tube opening 568. Inner tube body 560 includesan internal rod channel 567 that connects first and second inner tubeopenings 566/568, respectively. As shown in FIGS. 21A and 21C, innertube 505 comprises a first inner tube slot 565 a and a second inner tubeslot 565 b diametrically opposed to first inner tube slot 565 a. Innertube body 560 also comprises a first inner tube channel 569 a and asecond inner tube channel 569 b as shown in FIG. 21B. Inner tube body560 comprises a first finger slot 561 a and a second finger slot 561 bdiametrically opposed to first finger slot 561 a disposed therein forreceiving the fingers 510.

Also, a first left spring pocket 906 a and a first right spring pocket904 a are disposed within inner tube body 560, adjacent to and onopposite sides of first finger slot 561 a, for receiving finger springs511. Similarly, a second left spring pocket 906 b and a second rightspring pocket 904 b are disposed within inner tube body 560, adjacent toand on opposite sides of second finger slot 561 b, for receiving fingersprings 511. In addition, inner tube body 560 comprises finger pinapertures 900 for receiving finger hinge pins 515, and spring pinapertures 902 for receiving spring hinge pins 513.

Referring to FIGS. 22A-22C, retractor sleeve 506 of reduction device 600is shown. Retractor sleeve 506 comprises a hollow, cylindrical-shapedretractor sleeve body 570, having a first retractor sleeve end 572 and asecond retractor sleeve end 574 opposite first retractor sleeve end 572.Retractor sleeve 506 further comprises a first retractor sleeve arm 571extending longitudinally away from first retractor sleeve end 572 ofretractor sleeve body 570 and a second retractor sleeve arm 573extending longitudinally away from first retractor sleeve end 572, butdiametrically opposed to first retractor sleeve arm 571 along theretractor sleeve body 570. Additionally, retractor sleeve 506 comprisesa third retractor sleeve arm 575 extending longitudinally away fromsecond retractor sleeve end 574 of retractor sleeve body 570 and afourth retractor sleeve arm 577 extending longitudinally away fromsecond retractor sleeve end 574, but diametrically opposed to thirdretractor sleeve arm 575 along retractor sleeve body 570. Additionally,a release spring support ring 578 is formed by a lip disposed around theinterior periphery of the retractor sleeve body 570 between the firstretractor sleeve end 572 and the second retractor sleeve end 574. Therelease spring support ring 578 abuts the release spring 517 uponassembly and prevents translation of the release spring.

Referring to FIG. 23, reduction sleeve 507 of reduction device 600 isshown. Reduction sleeve 507 comprises a hollow, cylindrical shapedreduction sleeve body 580, having a first reduction sleeve end 582 and asecond reduction sleeve end 584 opposite first reduction sleeve end 582.First reduction sleeve end 582 comprises a first reduction sleeveopening 586, and second reduction sleeve end 584 comprises a secondreduction sleeve opening 588. Reduction sleeve body 580 includes aninternal reduction sleeve channel 587 that connects first and secondreduction sleeve openings 586 and 588, respectively. As shown in thefigures, reduction sleeve 507 comprises reduction rod engagement slots581 running from first reduction sleeve end 582 longitudinally along aportion of reduction sleeve body 580. It is envisioned in an embodimentthat there are two reduction rod engagement slots 581 disposed alongreduction sleeve body 580 diametrically opposed to each other.

Along the same sides of reduction sleeve body 580 as reduction rodengagement slots 581, reduction sleeve viewing apertures 583 arepositioned adjacent to and/or near second reduction sleeve end 584.Reduction sleeve body 580 also comprises a rod engagement radius 585disposed therein and at the distal end of second reduction sleeve end584 and another rod engagement radius 585 disposed therein and at thedistal end of second reduction sleeve end 584. Reduction sleeve body 580further comprises reduction sleeve radial reductions 589 disposedtherein and at the distal end of second reduction sleeve end 584, offset90° from rod engagement radii 585.

Referring to FIGS. 24A and 24B, release ring 508 of reduction device 600is shown. Release ring 508 comprises a hollow, cylindrical shapedrelease ring body 590, having a first release ring end 592 and a secondrelease ring end 594 opposite first release ring end 592. First releasering end 592 comprises a first release ring opening 596, and secondrelease ring end 594 comprises a second release ring opening 598.Release ring body 590 includes an internal release ring channel 597 thatconnects first and second release ring openings 596/598, respectively.Additionally, release ring 508 may comprise a first release ring feature591 disposed within release ring body 590 about the circumference ofrelease ring body 590 and a second release ring feature 593 disposedwithin release ring body 590 about the circumference of release ringbody 590, adjacent to first release ring feature 591. Release ring 508may also comprise at least one release ring screw aperture 595 disposedwithin release ring body 590 for receiving release ring screw 509. In anembodiment release ring 508 comprises two diametrically opposed releasering screw apertures 595 for receiving release ring screws 509.

Referring back to FIG. 16C, reduction device 600 comprises a two fingers510 diametrically opposed to each other. Now referring to FIGS. 25A-25D,finger 510 comprises a finger body 660 having a finger first end 662 anda finger second end 664 opposite finger first end 662. Finger second end664 comprises a finger hook 661 having a finger hook undercut 663. Inone example, finger hook undercut 663 may comprise any angle α above anacute angle. In another example, finger hook undercut 663 may comprisean angle α from about 20° to 90°, from about 30° to about 80°, fromabout 45° to about 75°. In still another example, finger hook undercut663 may comprise an angle α from about 40°, about 50°, about 60°, about70°, about 80°, or about less than 90°.

Finger body 660 comprises a finger aperture 665 disposed therethrough.Finger body 660 also comprises a first finger extension 670 extendinglongitudinally from finger body 660 and a second finger extension 672extending longitudinally from finger body 660 opposite to and spacedapart from first finger extension 670. First finger extension 670comprises a first finger stop 676 disposed at finger first end 662extending transversely from finger body 660. Second finger extension 672comprises a second finger stop 678 disposed at finger first end 662extending transversely from finger body 660.

Referring specifically to FIG. 25D along with FIGS. 25A-25C, first andsecond finger extensions 670 and 672 each comprise a finger slot 680.The finger slot 680 comprises three zones: a first zone A, a transitionzone B and a third zone C. In particular, first zone A of the slotcomprises a width that is configured and sized such that when finger campin 514 is positioned within first zone A, finger cam pin 514 forms arunning and sliding fit within first zone A. As example, the width offirst zone A is defined by upper slot guide 682 and lower slot guide 684and is sufficient enough to permit finger cam pin 514 to slide withinfirst zone A, but not enough to permit substantial lateral movementtransverse to the sliding movement of finger cam pin 514 within firstzone A. Substantial lateral movement is defined as movement greater than1/10^(th) the diameter of the finger cam pin 514. Third zone C of fingerslot 680 is configured and sized such that it has a width to form aclearance fit with finger cam pin 514. As an example, third zone C isconfigured to have a funnel shape such that its shape and size creates asmooth transition from the first zone's width to the maximum width ofthird zone C. Transition zone B provides a smooth transition from thewidth of the first zone A (i.e., running and sliding fit) to the widthof third zone C (i.e., clearance fit). In operation, finger cam pins 514are positioned within finger slots 680 such that the finger cam pinsengage and run along respective inner finger cam surfaces 688 of fingerslots 680. This action will be explained in greater detail below herein.

As such, when fingers 510 are in the spring-biased radially inwardlyposition (i.e., a normal position), finger cam pin 514 are positioned inthe third zone C formed by finger cam 686. When reduction device 600 ismoved such that second assembly opening 608 is slid over a tulip head ofa polyaxial screw 230 or a uniaxial pedicle screw, the tulip head, wheninserted into second assembly opening 608, engages the finger hooks 661of fingers 510 and forces and/or pushes them outwardly against the forceof finger springs 511. As the fingers 510 are pushed outwardly, thefingers pivot about finger hinge pins 515 such that finger first ends662 move radially inward, causing finger cam pins 514 (which are stillpositioned within third zone C and engaged against respective innerfinger cam surfaces 688 to move away from engagement with respectiveinner finger cam surfaces 688 within third zone C up and, optionally toengagement with respective outer finger cam surface 689. The clearancefit of third zone C provides the clearance to permit the fingers 510 topivot within rod reduction device 600 in order to permit the tulip headof pedicle screw 230 to insert into second assembly opening 608 of rodreduction device 600.

Referring to FIGS. 26A-26D, weld sleeve 516 is shown. Weld sleeve 516comprises a hollow, cylindrical-shaped weld sleeve body 730 having afirst weld sleeve end 732 and a second weld sleeve end 734. Disposed atfirst weld sleeve end 732, body comprises a first weld sleeve opening736, a second weld sleeve opening 738, and an internal weld sleevechannel 737 connecting the two openings. Weld sleeve body 730 comprisesdiametrically opposed retractor sleeve arm engagement slots 733. Secondweld sleeve end 734 includes a weld sleeve flange 731.

Referring to FIG. 27, finger cover 519 of reduction device 600 is shownhaving a finger cover body 750. Finger cover body 750 includes a fingercover aperture 752 and is curved to closely match the curvature of oneor more of the other components.

Referring to FIGS. 28A-30C as well as all the figures previouslyreferenced, the assembly of rod reduction device 600 will be described.As shown in FIGS. 28A and 28B, first and second finger extensions 670and 672 of finger 510 are inserted about third retractor sleeve arm 575of retractor sleeve 506. Finger cam pin 514 is inserted through fingerslot 680 of first finger extension 670, a third retractor sleeve armcross pin aperture 1000 a disposed within third retractor sleeve arm575, and through finger slot 680 of second finger extension 672.Similarly, first and second finger extensions 670 and 672 of finger 510are inserted about fourth retractor sleeve arm 577 of retractor sleeve506. A finger cam pin 514 is also inserted through finger slot 680 ofsecond finger extension 672, a fourth retractor sleeve arm cross pinaperture 1000 b disposed within fourth retractor sleeve arm 577, andthrough finger slot 680 of second finger extension 672.

Referring to FIGS. 29A and 29B, the retractor sleeve 506 and finger 510assembly is inserted over second inner tube end 564 of inner tube body560 such that fingers 510 slide into first and second finger slots 561a/561 b. Next, as an example, finger springs 511 are placed within firstleft spring pocket 906 a and first right spring pocket 904 a. One end offinger spring 511 is abutted against a surface of first right springpocket 904 a and the opposite end of finger spring 511 is abuttedagainst first finger stop 676. One end of finger spring 511 is abuttedagainst a surface of first left spring pocket 906 a and the opposite endof finger spring 511 is abutted against second finger stop 678. Fingersprings 511 are aligned with spring pin apertures 902 and then springhinge pins 513 are press fit into the aligned respective spring pinapertures 902 and spring coils. Also, finger aperture 665 is alignedwith finger pin aperture 900 and then finger hinge pin 515 is press fitinto and through such aligned apertures. The same assembly is performedfor the second finger 510. Once assembled, the pins are welded in placeusing conventional welding processes such as a laser welding process.Pin ends are then polished to be flush with outer surface of inner tube505.

In such a configuration, finger springs 511 bias fingers 510 radiallyinward toward a central longitudinal axis of reduction device 600 suchthat finger hook undercuts 663 of fingers 510 engage tulip head pockets236 disposed within and on opposite sides of the tulip head 234. Tuliphead pockets 236 include respective tulip head undercuts 238 thatcorrespond to and engage with finger hook undercuts 163 as shown in FIG.32B for example.

Release spring 517 is slid over second inner tube end 564 of inner tubebody 560 of inner tube 505 as shown in FIG. 29B. Next, align retractorsleeve arm engagement slots 733 of weld sleeve 516 with respective firstand second arms 571/573 of retractor sleeve 506 and then slide weldsleeve 516 over second inner tube end 564 of inner tube body 560 untilweld sleeve flange 731 of weld sleeve 516 is flush with retractor sleevebody 570 as shown in FIGS. 29A and 29B. Finger cover bodies 750 are fitinto respective first and second finger slots 561 a/561 b as shown inFIGS. 29A and 29B and then may be connected to inner tube body 560 inany number of conventional means such as, for example, welding (e.g.,laser welding around periphery of finger cover), snap-fit, etc.

Referring to FIGS. 16A-16C and 530, release ring 508 is slid overhousing tube 501. Reduction rod 503 is inserted into housing tube 501 asshown in FIG. 30 such that first and second extenders 548 a/548 b ofreduction rod 503 are inserted through and extend from housing tubeslots 526 of housing tube 501. Next, retractor sleeve 506/inner tube505/weld sleeve 516/fingers 510 assembly shown in FIGS. 29A and 29B isinserted into second end 524 of housing tube 501 such that first andsecond arms 571/573 of retractor sleeve 506 align with and slide intosecond housing tube slots 529 of housing tube 501 as shown in FIG. 30.Weld sleeve 516 is connected to housing tube 501 via conventionalconnection methods, including welding. Additionally, first and secondscrews 509 a/509 b are inserted through and threadably engaged withrelease ring 508, housing tube 501, and respective first and secondretractor sleeve arms 571/573. Engagement with first retractor sleevearm 571 and second retractor sleeve arm 573 is through first retractorsleeve arm screw aperture 579 a and second retractor sleeve arm screwaperture 579 b respectively.

Referring to FIGS. 30A-30C, the final assembly of reduction device 600is shown. Specifically, reduction sleeve 507 is slid over second end 524of housing tube 501 such that reduction rod engagement slots 581 abutagainst and are welded to first and second extenders 548 a and 548 b ofreduction rod 503. Advancing knob 502 is inserted into housing tubefirst end 522 of housing tube 501, a plurality of ball bearings 518 aredisposed into advancing knob bearing well 539 of advancing knob annularring 538 of advancing knob 502, and then cap 504 is threadably engagedto housing tube first end 522 of housing tube 501. The cap bearing well555 interfaces with the ball bearings 518 opposite the advancing knobbearing well 539.

Referring to FIGS. 33A and 33B, a reduction adaptor 1100 is shown.Reduction adaptor 1100 includes at a first end, an internal hexagonalhead (e.g., similar to a socket head), and at a second end, an externalhexagonal end, opposite the first end. It is understood that othertypes, configurations, and shapes of heads can be used. The first endcan be inserted onto advancing knob first end 532 of advancing knob 502to engage advancing knob engagement head 536 of advancing knob 502 asshown in FIGS. 33A and 33B.

Referring to FIGS. 40A-40C, an embodiment of pedicle screw 230, size andshape of the pedicle screw 230 and the second assembly opening 608 ofthe reduction device 600 substantially match. When the tulip head 234 ofthe pedicle screw 230 is inserted into second assembly opening 608 ofsecond end 604 of device 600 the pedicle screw 230 is engaged withminimal freedom of movement. As such, in one embodiment, the clocking ofreduction device 600 to the tulip head 234 of the pedicle screw 230 isfrom about 0° to about 20°, from about 0° to about 15°, from 0° to about10°, or from 0° to about 5°. As shown, fingers 510 are engagingrespective tulip head pockets 236 of the tulip head 234. The tulip head234 and corresponding second assembly opening 608 of device 600 has across sectional shape that is substantially rectilinear, having roundedcorners and curved sidewalls.

Referring to FIG. 31, a set screw driver 850 is shown. Set screw driver850 includes a set screw driver body 852 having a set screw engagementhead 854 and a driver head 856. In this example, set screw engagementhead 854 includes an external head that has a star-shape which matchesand/or corresponds with the internal star-shaped head of the set screw.Driver head 856 comprises a substantially square-shaped head. However,it is understood that the heads of the driver and/or the set screw headcan have either internal and/or external heads having any shape, size,and/or configuration.

A method for reducing a rod within a tulip head of a pedicle screw usingthe reduction device 600 is shown and described herein. FIGS. 32A-34Care sequential steps in the process of this method for reducing a spinalrod 112/114 into a tulip head 234 of a pedicle screw 230. Such a methodmay be part of a method for correcting or ameliorating spinalaberrations or defects such as, for example, scoliosis, lordosis, and/orkyphosis.

FIGS. 32A-34C show the tulip head of pedicle screw 230 fully insertedinto second assembly opening 608 of reduction device 600 and in lockedengagement, i.e., fingers 510 are fully inserted into respective tuliphead pockets 236 on opposite sides of the tulip head 234 such thatfinger hook undercuts 663 of the fingers 510 are engaged with respectivetulip head undercuts 238 of the tulip head pockets 236 of the tulip head234. In the embodiment shown in FIGS. 40A-40C, the tulip head pockets236 of the tulip head 234 do not extend transversely all the way acrossthe tulip head. Thus, in this illustrative example, the tulip headpockets 236 have an upper wall which includes the tulip head undercut238, a lower wall, and two opposed side walls. However, it is understoodthat other configurations may be utilized such as, for example, no sidewalls and/or bottom wall.

When release ring 508 is pulled toward first end 602 of device 600, itpulls retractor sleeve 506 respective toward first end 602 which causesfinger cam pins 514 to slide along inner finger cam surfaces 688 fromthird zone C through transition zone B and into first zone A, pullingfingers 510 radially outwardly from the tulip head. When the finger campins 514 have slide into zone C, fingers 510 are moved into the unlockposition, disengaging finger hook undercuts 663 from the correspondingtulip head undercuts 238 of the tulip head pockets 236 of the tulip head234. In this unlocked position, the tulip head 234 may be removed fromthe reduction device 600.

Referring to FIGS. 35A and 35B, an embodiment of a rod reductionassembly 450 is shown. Advancing wheel 456 is in threaded engagementwith outer reducer shell 454. Rotation of advancing wheel 456 forcesmovement of reduction arm 452 relative to the outer reducer shell 454.

Referring to FIGS. 36A and 36B, an embodiment of a provisional lockinginstrument 360 is shown. The provisional locking instrument 360 isinserted into the central shaft of the rod reduction assembly 450 andprovisional locking instrument threads 368 are engaged with internal rodreduction threads 458. The threaded engagement advances the provisionallocking assembly through the rod reduction assembly 450. The provisionallocking instrument 360 further comprises a locking sheath 362 whichengages the tulip head 234 of a pedicle screw 230 advances the tuliphead undercuts 238 against flanged catches of the reduction arm 452. Asthe provisional locking instrument 360 is advanced, the locking sheath362 engages the tulip head 234 and ceases advancing. Continued advancingof the provisional locking instrument 360 exposes polyaxial lockingtines 364 which engage the screw shaft locking mechanism of the pediclescrew 230. The polyaxial locking tines 364 are generally concealed bythe locking sheath 362 which is held in a forward position by anadvancing spring 366.

Referring to FIGS. 37A-38, an embodiment of a pedicle screw inserter 380is shown. The pedicle screw inserter 380 is used to insert a pediclescrew, for example a polyxial screw 230, into a patient. The pediclescrew inserter 380 comprises a central tightening shaft 382, a handle384, a friction sleeve 386, and a screw head engagement sleeve 388. Thecentral tightening shaft 382 has a driver tip 394 shaped to match thedrive head of the pedicle screw shaft. For example. The driver tip 394may be a hexalobe. The screw head engagement sleeve 388 has screw headengagement threads 390. The screw head engagement threads mate with theinternal threads of a pedicle screw to secure the screw head engagementsleeve 388 and a pedicle screw together. The handle 384 and frictionsleeve 386 allow for free rotation of the central tightening shaft 382.

To insert a pedicle screw the screw head engagement sleeve 388 isengaged with the head of a pedicle screw. The driver tip 394 of thecentral tightening shaft 382 is aligned with the mating feature of thepedicle screw. The friction sleeve 386 and handle 384 are moved alongthe central tightening shaft until the friction sleeve interlocks withthe head of the pedicle screw as shown in FIG. 38. The centraltightening shaft 382 is rotated which rotates the shaft of the pediclescrew through the engagement with the driver tip 394. The interlockbetween the friction sleeve 386 and the head of the pedicle screw helpsprevent the screw head engagement sleeve from unthreading during thepedicle screw insertion process. The friction sleeve 386 and centraltightening shaft 382 rotate in unison as they are both engaged with thehead of the pedicle screw.

An exemplary method of therapy for use of the present devices isdescribed as follows:

Initially, the area of implantation is surgically approached.

For a pedicle screw correction technique, a thoracic facetectomy isperformed. The facet joints are cleaned and rongeurs are used to performa partial inferior articular process osteotomy. This is done to enhancevisualization. 3 mm to 5 mm of the inferior facet is removed and thearticular cartilage of the superior facets is removed, except for on thelowest vertebra to be instrumented. This allows for the intraoperativelocalization of the thoracic pedicle screw starting points and enhancesfusion.

The pedicles are subsequently prepared. A pedicle awl or burr is used tocreate a 3 mm deep posterior cortical breach. The pedicle awl may beadvanced by gently twisting the handle with light pressure. A pedicleblush may be visualized suggesting entrance into the cancellous bone atthe base of the pedicle but the blush may not be evident when preparingsmall pedicles due to the limited intrapedicular cancellous bone. Whenno pedicle blush is visualized, use a straight or curved pedicle probe,a Lenke probe for example, to search in the cortical breach for thesoft, funnel-shaped cancellous bone, which indicates the entrance to thepedicle. This procedure should be performed with the tip of the pedicleprobe pointed laterally to avoid perforation of the medial cortex.Gripping the sides of the handle to avoid applying too much ventralpressure, the tip of the probe is inserted approximately 2 mm toapproximately 25 mm. The probe is oriented so that the flat surface ofthe probe is in the same plane as the curve of the pedicle, then removedand reinserted with the tip pointed medially. The probe is advanced tothe desired depth and rotated approximately 180° to ensure adequate roomfor a screw. The feeler probe is advanced to the base of the hole,alternatively called the floor, to confirm five distinct bony borders.The five bony borders being a floor and four walls (medial, lateral,superior, and inferior). When necessary, bone wax or other hemostaticagent may be placed in the pedicle hole to limit bleeding, and then theprobe may be repositioned with a more appropriate trajectory.

The pedicle is undertapped for the appropriate screw size. After thepedicle is undertapped a flexible feeler probe may be used to verifypresence of threads in the tapped hole. To measure the length of thehole, a feeler probe is advanced to the floor of the hole and a hemostatis clamped to the feeler probe at the point where it exits the pedicle.The appropriate screw diameter and length may subsequently be selectedbased on both preoperative measurement and intraoperative observation.The same technique is repeated for each of the remaining pedicles thatneed to be instrumented.

Roentgenographic assistance using plain radiographs or fluoroscopy maybe utilized to ensure proper screw trajectory. Pedicle markers areplaced into the holes of the pedicles and a lateral view is obtained. Ananterior-posterior view may also be obtained.

Pedicle screws 230 are placed in each prepared pedicle. Selection ofuniaxial or polyaxial screws 230 is at the discretion of the surgeonwith both options being anticipated. The screws should be advancedslowly through the pedicle to ensure proper tracking. The pedicle screws230 should be placed at every segment that allows free passage of apedicle screw on the correction side of the spine and every third orfourth level on the supportive side. At the proximal and distal end ofthe supportive side at least two screws should be inserted. Addition ofmore screws will result in greater construct rigidity. Upon placement ofthe screws they should be checked radiographically to ensureintraosseous screw placement. Should it be determined that a pedicle istoo narrow to cannulate, alternate fixation methods such as hooks 210,220, wires or tapes may be used.

Once correct pedicle screw placement has been verified radiographically,the spinal rods 112, 114 are prepared. The spinal rods 112, 114 aremeasured and contoured in the sagittal and coronal planes. Whencontouring, the spinal rods 112, 114 may be clamped at both ends withrod grippers to help prevent the rod from rotating.

Once prepared to the proper contour and length, the first rod is placedinto the previously inserted screws. To reduce the rod and seat it intoeach previously placed pedicle screw a rocker, a rod reduction assembly450, or a reduction device 600 may be used. The rocker method is aneffective method for reducing the rod into the implant when only aslight height difference exists between the rod and the implant saddle.To reduce the rod using the rocker method, the sides of the implant aregrasped with the rocker cam above the rod. The rocker is leveredbackwards over the rod to seat the rod into the saddle of the implant. Aset screw is subsequently placed and provisionally tightened to hold therod in place.

For reduction of the rod using the rod reduction assembly 450, with thepedicle screw and rod in place the rod reduction assembly is appliedover the head of the screw. The provisional locking instrument 360 isinserted down the tube of the rod reduction assembly 450 and threadeddown to engage the provisional locking feature. Alternatively, theprovisional locking instrument 360 may be inserted down the tube of therod reduction assembly 450 and partially threaded down prior to affixingthe rod reduction assembly to the screw head. The rod is then reduced byturning the advancing wheel 456 of the rod reduction assembly 450. Ifgreater torque is required to reduce the rod, a reduction adaptor 1100attached to an axial or torque limiting T-handle may interface with theadvancing wheel 456 of the rod reduction assembly 450. The provisionallocking instrument is subsequently removed as the rod reduction assemblyhas taken over the provisional lock engagement. A set screw driver 850is used to introduce a set screw. The set screw is passed down thecentral cavity of the rod reduction assembly 450 until it bottoms out onthe screw threads. To avoid cross threading of the set screw, the setscrew is turned counterclockwise until a click is felt and then turnedclockwise to tighten.

For reduction of the rod using the rod reduction device 600, with thepedicle screw and rod on place the red reduction device is applied overthe tulip head 234 of the screw. The fingers 510 of the rod reductiondevice 600 engage the tulip head pockets 236 of the pedicle screw tuliphead 234. The rod is then reduced by turning the advancing knob 502 ofthe rod reduction device 600. If greater torque is required to reducethe rod, a reduction adaptor 1100 attached to an axial or torquelimiting T-handle may interface with the advancing knob 502 of the rodreduction device 600. A set screw driver 850 is used to introduce a setscrew. The set screw is passed through the first assembly opening 606 ofthe rod reduction device 600 until it bottoms out on the screw threads.To avoid cross threading of the set screw, the set screw is turnedcounterclockwise until a click is felt and then turned clockwise totighten.

While leaving the set screws loose or only locked at one end, the spinalrod 112, 114 is slowly straightened using tubular benders. Fullystraightening the spinal rod 112, 114 may require several passes.

Once the contoured rod and all the set screws have been placed, thecontoured rod is rotated into its final position. The rotation must bedone slowly to prevent rapid neurologic changes and/or injury to thespinal cord. Using two rod holders the contoured rod is rotated into thedesired position. The apical set screws are tightened and compression ordistraction may be performed. During all the correction maneuvers thescrew and bone interface should be monitored.

The second rod and its respective set screws are placed according to thetechniques previously outlined. Following placement of the second rodand set screws, convex compressive forces are placed on the segmentsusing a parallel compressor to horizontalize the lowest instrumentedvertebra and mildly compress the convexity of the deformity. It ispreferred that compression be released just prior to final tightening.This technique helps ensure that the implant head and rod are normalizedto one another and allows for the rod to be fully seated in the implanthead during the final tightening step.

With all rods and screw placed and provisionally secured with setscrews, the set screws are tightened to their final torque. The countertorque wrench and the set screw driver 850 are placed onto the openscrew, saddle, and set screw. A torque limiting T-handle is placed onthe set screw driver 850 and turned clockwise while firmly holding thecounter torque wrench. The torque liming T-handle is preferably set to70 in-lbs. The T-handle is turned clockwise until an audible click isheard indicating the proper torque has been met.

After final tightening of the set screws, cross connectors are placed.The cross connector connection provides rotational stability to theconstruct as a framed construct resists rotational forces. The crossconnectors should be placed close to the construct extremities butplacement at other positions along the construct is also envisioned.

Bi-axial cross connectors 330 are affixed to the spinal rods 112, 114 bycapturing a rod in each of the cross connector rod hooks 322 at the endof each linkage 334, 336. Prior to attaching the bi-axial crossconnector 330 to the spinal rods 112, 114 the midline nut 338 or midlinelocking screw 339 is provisionally tightened. A first rod is captured inthe cross connector rod hook 322 at the end of one of the linkages 334,336 and the conical screw 302 is provisionally tightened to anchor thedevice to the rod. The midline nut 338 or midline locking screw 339 isloosened to allow the linkages 334, 336 to angulated and lengthen orshorten. A second rod is captured in the cross connector rod hook 322 atthe end of the other linkage 334, 336 and the conical screw 302 isprovisionally tightened. The midline nut 338 or midline locking screw339 is re-tightened to secure the linkages 334, 336 of the bi-axialcross connector 330. For final tightening of the conical screw 302, thecounter torque tube and screw driver are placed onto the bi-axial crossconnector 330, spinal rod 112, 114, and conical screw. A torque limitingT-handle is placed on the driver shaft and turned clockwise while firmlyholding the counter torque wrench. The torque liming T-handle ispreferably set to 50 in-lbs. The T-handle is turned clockwise until anaudible click is heard indicating the proper torque has been met.

Fixed cross connectors 300 are affixed to the spinal rods 112, 114 byplacing the fixed cross connector over the rods such that a rod isseated in each cross connector rod hook 322. The conical screws 302 areprovisionally tightened and then finally tightened using a countertorque tube, driver shaft, and torque limiting T-handle as with thebi-axial cross connectors 330. For some applications, the fixed crossconnector extension rod 304 of the fixed cross connector 300 may need tobe bent to fit the anatomy and spinal rod 112, 114 arrangement.

For a hook 210, 220 based correction technique, the surgical site isprepared by dividing the facet capsule. A portion of the inferior facetprocess may also be removed to facilitate insertion of the hook 210,220. The pedicle should be clearly identified with the help of a pedicleelevator. The pedicle hook may be inserted from T1 to T10 with the hookblade 212 cephalad and in the infralaminar position. The hook blade 212of the hook 210, 220 should wrap around the pedicle and not split theinferior articular process. To assist in position the pedicle hook, ahook pusher may be utilized.

For hook placement at the transverse process a wide blade hook istypically used in a pedicle-transverse claw construct as a caudal hook.Laminar hook trials may be used to separate the ligamentous attachmentbetween the undersurface of the transverse process and the posteriorarch of the rib medial to the rib-transverse joint. The hook is theninserted using a hook holder.

For placement of thoracic hooks a partial or total division of thespinous process directly above the vertebra to be instrumented may beperformed. A division and/or partial removal of the ligamentum flavumand a small laminotomy are carried out on the superior lamina. Theamount of bone removed from the lamina may vary depending on the size ofthe hook blade 212 and throat angle chosen. The upper edge of the laminabelow or the lower edge of the lamina above may be resected to easeplacement of the hook 210, 220. A laminar hook trial may also be used tocheck the space between laminar and peridural structures. When placing ahook 210, 220 on the superior lamina a hook should be used to insert thehook.

With all the appropriate hooks placed on the side of the deformity to becorrected, a rod template is used to measure the length and curve. Thespinal rod 112, 114 on the corrective side should be cut 2-3 cm longerthan the actual length to leave adequate length for correction. Thespinal rod 112, 114 is then bent into the correct orientation using afrench bender or tubular benders.

Any hooks 210, 220 which are not stable prior to spinal rod 112, 114insertion should be removed until placement of the rod.

The spinal rod 112, 114 and set screws 120 are placed and provisionallytightened according to the same technique outlined for pedicle screws.Rotation, in-situ bending, compression, and distraction maneuvers may becompleted undertaken. During rod rotation it is important to monitor theinterval hooks as they tend to back out.

Upon completion of the deformity correction and the seating of thecorrection rod, the opposite side of the construct is prepared. Using afrench bender, the rod for the opposite side of the construct iscontoured according to the curvature of the spine and the residualposition of alignment from the correction rod. The contoured rod isplaced into the hooks 210, 220 with the rod holder or by hand andprovisionally secured with set screws 120. With the spinal rod 112, 114secured to the implants, distraction and/or compression is performed toplace the hooks 210, 220 into their final position. The set screws 120are subsequently finally tightened according to the technique previouslydiscussed for pedicle screws and cross connectors 300, 330.

Cross connectors 300, 330 are preferably also added to the construct foradded rotational stability.

This is simply an exemplary surgical technique and other known andaccepted methods or techniques for performing steps outlined within thetechnique may be substituted where appropriate.

The previous text sets forth a broad description of numerous differentembodiments. The description is to be construed as exemplary only anddoes not describe every possible embodiment since describing everypossible embodiment would be impractical, if not impossible, and it willbe understood that any feature, characteristic, component, step ormethodology described herein can be deleted, combined with orsubstituted for, in whole or part, any other feature, characteristic,component, step or methodology described herein. Numerous alternativeembodiments could be implemented, using either current technology ortechnology developed after the filing date of this patent, which wouldstill fall within the scope of the claims.

It should also be understood that, unless a term is expressly defined inthis specification using the sentence “As used herein, the term ‘______’is hereby defined to mean . . . ” or a similar sentence, there is nointent to limit the meaning of that term, either expressly or byimplication, beyond its plain or ordinary meaning, and such term shouldnot be interpreted to be limited in scope based on any statement made inany section of this patent (other than the language of the claims). Noterm is intended to be essential unless so stated. To the extent thatany term recited in the claims at the end of this patent is referred toin this patent in a manner consistent with a single meaning, that isdone for sake of clarity only so as to not confuse the reader, and it isnot intended that such a claim term be limited, by implication orotherwise, to that single meaning. Finally, unless a claim element isdefined by reciting the word “means” and a function without the recitalof any structure, it is not intended that the scope of any claim elementbe interpreted based on the application of 35 U.S.C. §112, sixthparagraph or similar doctrine.

It is also noted that recitations herein of “at least one” component,element, etc., should not be used to create an inference that thealternative use of the articles “a” or “an” should be limited to asingle component, element, etc.

It is noted that recitations herein of a component of the presentdisclosure being “configured” to embody a particular property, orfunction in a particular manner, are structural recitations, as opposedto recitations of intended use. More specifically, the references hereinto the manner in which a component is “configured” denotes an existingphysical condition of the component and, as such, is to be taken as adefinite recitation of the structural characteristics of the component.

It is noted that terms like “preferably,” “commonly,” and “typically,”when utilized herein, are not utilized to limit the scope of the claimedinvention or to imply that certain features are critical, essential, oreven important to the structure or function of the claimed invention.Rather, these terms are merely intended to identify particular aspectsof an embodiment of the present disclosure or to emphasize alternativeor additional features that may or may not be utilized in a particularembodiment of the present disclosure.

For the purposes of describing and defining the present invention it isnoted that the terms “substantially” and “approximately” are utilizedherein to represent the inherent degree of uncertainty that may beattributed to any quantitative comparison, value, measurement, or otherrepresentation. The terms “substantially” and “approximately” are alsoutilized herein to represent the degree by which a quantitativerepresentation may vary from a stated reference without resulting in achange in the basic function of the subject matter at issue.

Having described the subject matter of the present disclosure in detailand by reference to specific embodiments thereof, it is noted that thevarious details disclosed herein should not be taken to imply that thesedetails relate to elements that are essential components of the variousembodiments described herein, even in cases where a particular elementis illustrated in each of the drawings that accompany the presentdescription. Rather, the claims appended hereto should be taken as thesole representation of the breadth of the present disclosure and thecorresponding scope of the various inventions described herein. Further,it will be apparent that modifications and variations are possiblewithout departing from the scope of the invention defined in theappended claims. More specifically, although some aspects of the presentdisclosure are identified herein as preferred or particularlyadvantageous, it is contemplated that the present disclosure is notnecessarily limited to these aspects.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made. It istherefore intended to cover in the appended claims all such changes andmodifications.

1. A medical device, the medical device comprising a spinal rodreceiving channel and a rod retaining set screw; wherein, the spinal rodreceiving channel comprises at least a first circular hole, a secondcircular hole, and a third circular hole; the first circular hole, thesecond circular hole, and the third circular hole are parallel; thefirst circular hole, the second circular hole, and the third circularhole have offset centers disposed along a single line; the firstcircular hole forms an upper arc of the rod receiving channel; thesecond circular hole forms a middle arc of the rod receiving channel;the third circular hole forms a lower arc of the rod receiving channel;the middle arc and the lower arc are connected by a connecting slant;and the rod retaining set screw secures a spinal rod disposed in thespinal rod receiving channel into the medical device.
 2. The medicaldevice of claim 1, wherein the medical device comprises a plurality ofrod receiving channels disposed in parallel arrangement.
 3. The medicaldevice of claim 1, wherein the medical device comprises a single rodretaining set screw in combination with each rod receiving channel. 4.The medical device of claim 1, wherein the medical device comprises tworod retaining set screws in combination with each rod receiving channel.5. (canceled)
 6. (canceled)
 7. The medical device of claim 1, whereinthe medical device comprises a hook for engagement with the lamina of avertebra.
 8. The medical device of claim 1, wherein the medical devicecomprises a lateral connector rod with a diameter of approximately 4.75mm or 5.5 mm for engagement with a spinal pedicle screw.
 9. A medicaldevice, the medical device comprising a first cross connector rod hookand a second cross connector hook for securing spinal rods, two conicalscrew receiving ports, and two rod retaining conical screws; wherein,the first and second cross connector rod hooks each comprise at least afirst circular bore, a second circular bore, and a third circular borewhich in combination form a hook with an open portion; the firstcircular bore, the second circular bore, and the third circular bore areparallel; the first circular bore, the second circular bore, and thethird circular bore have offset centers disposed along a single line;the first circular bore forms an upper arc of each of the first crossconnector rod hook and the second cross connector rod hook; the secondcircular bore forms a middle arc of each of the first cross connectorrod hook and the second cross connector rod hook; the third circularhole forms a lower arc of each of the first cross connector rod hook andthe second cross connector rod hook; the middle arc and the lower arcare connected by a connecting slant; and the rod retaining conicalscrews secure a spinal rod disposed in the first and second crossconnector rod hooks into the medical device.
 10. (canceled) 11.(canceled)
 12. The medical device of claim 9, wherein the medical devicefurther comprises a first linkage, a second linkage, a pivot post, and amidline nut; wherein, the first linkage comprises the first crossconnector hook, one of the conical screw receiving ports and a bi-axialcross connector extension rod; the bi-axial cross connector extensionrod is a round shaft extending from the conical screw receiving port ofthe first linkage; the second linkage comprises the second crossconnector hook, one of the conical screw receiving ports and a bi-axialcross connector extension plank having a linkage retaining orifice; thelinkage retaining orifice is disposed proximal an end of the bi-axialcross connector extension plank distal the conical screw receiving portof the second linkage; the pivot post comprises a bi-axial crossconnector extension rod channel, a threaded post, and a linkageretaining shoulder; the bi-axial cross connector extension rod channelis configured to allow the bi-axial cross connector extension rod topass through unimpeded; and the bi-axial cross connector extension rodis disposed in the bi-axial cross connector extension rod channel, thelinkage retaining orifice is disposed over the threaded post, and themidline nut is disposed on the threaded post.
 13. The medical device ofclaim 12, wherein the bi-axial cross connector extension rod comprises aflared portion with a diameter larger than the diameter of bi-axialcross connector extension rod channel disposed at the end of thebi-axial cross connector extension rod distal from the first crossconnector hook.
 14. The medical device of claim 12, wherein the bi-axialcross connector extension rod channel comprises a first surface and asecond surface; the first surface is disposed proximal the threadedshaft and is an arc with a diameter of approximately 0.6 toapproximately 1.4 mm larger than the diameter of the bi-axial crossconnector extension rod and the second surface is disposed distal thethreaded shaft and is an arc with a diameter of approximately 0.03 toapproximately 0.3 mm larger than the diameter of the bi-axial crossconnector extension rod.
 15. The medical device of claim 9, wherein theopen portion of the first cross connector hook and the open portion ofthe second cross connector hook are oriented in the same direction. 16.The medical device of claim 9, wherein the open portion of the firstcross connector hook and the open portion of the second cross connectorhook are oriented in opposite directions.
 17. The medical device ofclaim 9, wherein the first cross connector hook, the second crossconnector hook, and their respective conical screw receiving ports areconnected by a cross connector extension rod of a predetermined length.18. A medical instrument, the medical instrument comprising a rodreduction assembly and a pedicle screw engaging assembly; wherein, therod reduction assembly comprises a rod reduction sleeve, a reductionrod, and an advancing knob; the reduction sleeve comprises a hollow,cylindrical shaped body having an internal reduction sleeve channel,reduction rod engagement slots on a first end, and rod engagement radiion a second end; the reduction rod comprises external reduction rodthreads on a first end and first and second extenders extending radialfrom the outer surface proximal a second end; the first and secondextenders engage with the reduction rod engagement slots; the advancingknob comprises internal threads matched to the external reduction rodthreads; the pedicle screw engaging assembly comprises fingers forengagement with the head of a pedicle screw, finger cam pins, an innertube, and a release ring; the fingers each comprise a finger hook havinga finger hook undercut, a finger slot, and a finger aperture; the fingerslot having a first end distal the finger hook with a width sufficientto permit finger cam pin to slide through but not enough for substantiallateral movement transverse to the sliding direction and a second endproximal the finger hook with a larger width to form a clearance fitwith the finger cam pin; the finger aperture disposed between the fingerhook and the finger slot; the inner tube comprises a hollow, cylindricalbody having a first inner tube end and a second inner tube end, a firstinner tube slot and a second inner tube slot diametrically opposedacross the cylindrical body, and a first finger slot and a second fingerslot diametrically opposed across the cylindrical body; the first innertube slot and the second inner tube slot are open toward the secondinner tube end; the fingers are disposed in the first finger slot andthe second finger slot with the fingers oriented to dispose the fingerhooks proximal the second inner tube end and the finger hook undercutstoward the interior of the inner tube; and movement of the release ringfrom a first position to a second position moves the finger cam pinsfrom the second end of the finger slot to the first end of the fingerslot thereby positioning the fingers for insertion of the head of apedicle screw.
 19. The medical instrument of claim 18, wherein thepedicle screw engaging assembly further comprises finger springs to biasthe finger hooks toward the interior of the inner tube.
 20. The medicalinstrument of claim 18, wherein the first finger slot and second fingerslot are circumferentially offset 90 degrees from the first inner tubeslot and the second inner tube slot.
 21. The medical instrument of claim18, wherein the finger hook undercut comprises an angle betweenapproximately 20 degrees and 90 degrees.
 22. The medical instrument ofclaim 18, wherein the pedicle screw engaging assembly further comprisesa retractor sleeve mechanically connecting the release ring and thefingers; the retractor sleeve comprising a first retractor sleeve armand a second retractor sleeve arm with first and second retractor sleevearm screw apertures for connection of the release ring and a thirdretractor sleeve arm and a fourth retractor sleeve arm with third andfourth retractor sleeve arm cross pin apertures for connection to thefingers via the finger cam pins.
 23. The medical instrument of claim 18,wherein the reduction rod further comprises an annular bulbous portionwith an increased outer diameter compared to the rest of the reductionrod.
 24. The medical instrument of claim 18, wherein the medicalinstrument further comprises finger covers disposed over the firstfinger slot and the second finger slot to conceal and protect thefingers.